Definition: In this task, you are given an input list A. You need to convert all the alphabets in the list with a number representing their position in the English alphabet. E.g., replace A by 1, B by 2, a by 1, b by 2, and so on.
Input: ['y', '7405', '289', 'f', 'Z', '7891', '1743']

25, 7405, 289, 6, 26, 7891, 1743